TMP92CF30
2009-06-12
92CF30-380
3.16.3.27 USBREADY Register
This register informs finishing writing data to descriptor RAM on UDC.
After assigned data to descriptor RAM, write “0” to bit0.
7 6 5 4 3 2 1 0
bit Symbol
USBREADY
Read/Write
R/W
USBREADY
(07E6H)
Reset
State
0
USBREADY (Bit0)
0: Writing to descriptor RAM has finished.
1: Writing to descriptor RAM is enabled.
(However, writing to descriptor RAM is prohibited when connected to host.)
Detect level of VDD signal from USB cable, and execute initialize sequence. In this
case, UDC disable detecting USB_RESET signal until USBREADY register is written
“0” after release of USB_RESET.
If the pull-up resistor on D
+
signal is controlled by control signal, when pull-up
resistor is connected to host in OFF condition, this condition is equivalent condition
with USB_RESET signal by pull-down resistor on the host side. Therefore UDC is not
detected in USB_RESET until “0” is written to USBREADY register
Note1: External pull-up resistor and control switch are needed with the TMP92CF30.
Note2: The above setting is an example for when communication. A specific circuit is required to prevent cullent flow
at connector detection , no-use, and no connection.
VDD
PortXX
(Pull-up on/off)
INTXX
Write signal
Descriptor RAM access
Device ID RAM
Register in USB
USBREADY registera access
GND
15 k
Ω
15 k
Ω
USB host
VCC
VSS
PortXX
D
+
D
−
CPU
UDC
R2
R3
R1 = 1.5 k
Ω
TMP92CF30
Summary of Contents for TLCS-900/H1 Series
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